Patent literature PTL 1 discloses detecting recumbence and standing when a cow is in heat (estrus) by communication between an RFID tag worn below a cow's abdomen and a reader/writer apparatus installed in a cattle shed. Since the reader/writer apparatus is installed in the cattle shed, however, detection is not possible during grazing.
Patent literature PTL 2 discloses detecting the mounting behavior of a cow in heat by inclination detection with an acceleration sensor. In the case of an acceleration sensor, however, it is necessary to wind a thick belt around the cow's torso to prevent erroneous detection caused, for example, by the cow shaking its skin when a horsefly or other insect approaches, or by misalignment of the acceleration sensor. The apparatus thus increases in size, placing a large burden on the cow.
Patent literature PTL 3 discloses using an inclination sensor to detect recumbence and standing when a cow is in heat. As with an acceleration sensor, however, it is necessary to wind a thick belt around the cow's torso to prevent erroneous detection caused by misalignment or the like. The apparatus thus increases in size, placing a large burden on the cow.
Patent literature PTL 4 discloses detection of heat by using a walking sensor to detect the number of steps a cow takes. As with an acceleration sensor, however, it is necessary to wind a thick belt around the cow's torso to prevent erroneous detection caused by misalignment or the like. The apparatus thus increases in size, placing a large burden on the cow.
Patent literature PTL 5 discloses detection of heat by using a motion sensor to detect the amount of activity of a cow. As with an acceleration sensor, however, it is necessary to wind a thick belt around the cow's torso to prevent erroneous detection caused by misalignment or the like. The apparatus thus increases in size, placing a large burden on the cow.
Patent literature PTL 6 discloses detection of heat by installing a reader/writer apparatus in a cattle shed and attaching a tag, such as an RFID, to a cow to detect the walking distance of the cow. Use is limited, however, since detection is not possible during grazing.
Patent literature PTL 7 discloses detection of heat by detecting movement by a cow with a movement sensor and a transmitter that transmits a signal from the movement sensor. As with an acceleration sensor, however, it is necessary to wind a thick belt around the cow's torso to prevent erroneous detection caused by misalignment or the like. The apparatus thus increases in size, placing a large burden on the cow.
Patent literature PTL 8 discloses detection of heat by using a walking sensor to detect the number of steps a cow takes. As with an acceleration sensor, however, it is necessary to wind a thick belt around the cow's torso to prevent erroneous detection caused by misalignment or the like. The apparatus thus increases in size, placing a large burden on the cow.
Patent literature PTL 9 discloses detection of heat by using a vibration sensor to detect the amount of activity of a cow. As with an acceleration sensor, however, it is necessary to wind a thick belt around the cow's torso to prevent erroneous detection caused by misalignment or the like. The apparatus thus increases in size, placing a large burden on the cow.
Patent literature PTL 10 discloses detection of heat by using a walking sensor to detect the number of steps a cow takes. As with an acceleration sensor, however, it is necessary to wind a thick belt around the cow's torso to prevent erroneous detection caused by misalignment or the like. The apparatus thus increases in size, placing a large burden on the cow.
Patent literature PTL 11 discloses detection of heat by using a pressure sensor attached to a cow's waist to detect the mounting behavior of the cow. It is not possible, however, to identify the mounting cow.
Patent literature PTL 12 discloses detection of heat by using a pressure responsive switch attached to a cow's spine to detect the mounting behavior of the cow. It is not possible, however, to identify the mounting cow.
Patent literature PTL 13 discloses the structure of a mounting fixture of a detection device for detecting the mounting behavior of a cow by using a pressure sensor attached to the cow's spine. It is not possible, however, to identify the mounting cow.
Patent literature PTL 14 discloses providing notification by light upon detecting mounting behavior of a cow with a pressure sensor attached to the cow. It is not possible, however, to identify the mounting cow.
Patent literature PTL 15 discloses the structure of a mounting fixture of a detection device for detecting the mounting behavior of a cow by using an acceleration sensor or an inclination sensor attached to the cow's backbone. However, it is necessary to wind a thick belt around the cow's torso to prevent erroneous detection caused by misalignment or the like. The apparatus thus increases in size, placing a large burden on the cow.
Patent literature PTL 16 discloses detecting recumbence and standing when a cow is in heat with a temperature sensor that detects the cattle shed temperature. Since the reader/writer apparatus is installed in the cattle shed, however, detection is not possible during grazing.
Patent literature PTL 17 discloses detecting that a cow is in heat with a temperature sensor that detects the temperature of the cow's vagina. However, the vaginal temperature cannot be measured during grazing, thereby limiting the circumstances in which this disclosure is applicable.
Patent literature PTL 18 discloses the transmission of ultrasonic waves from an ultrasonic transmitter attached to the neck of one cow to an ultrasonic receiver attached to the neck of another cow. PTL 18 discloses that upon ultrasonic waves being received by the ultrasonic receiver attached to the other cow's neck, the number of times ultrasonic waves are received is counted directly as the number of times the cow mounts (is mounted), i.e. the mounting (mounted) count. PTL 18 also discloses that electromagnetic waves or infrared rays may be used instead of ultrasonic waves. However, it is extremely difficult for the reception-enabling orientation of the ultrasonic receiver attached to the neck of the mounted cow to be matched properly with the orientation of transmission by the ultrasonic transmitter attached to the neck of the mounting cow. In particular at the time of mounting, the mounting cow lowers its head and places its chin on the back of the mounted cow. Accordingly, the mounting cow's chin blocks a signal with directivity, such as ultrasonic waves. Furthermore, the mounted cow often arches its back and lowers its head when being mounted. Therefore, the ultrasonic receiver is hidden by the mounted cow's back and cannot receive a signal with high directivity, such as ultrasonic waves. Mounting behavior cannot be detected in this case. Chin resting clearly cannot be detected either in this case.